CHICAGO (AP) -- Passengers are more dissatisfied with airlines' customer service than they have been in years at a time when carriers are charging more and more for tickets and services.
An annual survey being released Tuesday by the University of Michigan found customers giving airlines the worst grades since 2001, with the industry's overall scores dropping for the third straight year.
United Airlines and US Airways Group Inc., which are in talks to potentially combine into a single carrier, finished next-to-last and last, respectively, in the university's American Customer Satisfaction Index.
Continental Airlines Inc. and US Airways Group Inc. registered the biggest declines from 2007, both experiencing double-digit percentage drops.
A familiar bright spot in the results was Southwest Airlines Co., which led the industry in passenger satisfaction for the 15th consecutive year.
While unhappiness with airlines is nothing new, this year's survey produced "really dismal numbers," said Claes Fornell, a University of Michigan business professor and director of the research center that compiled the data.
"There's no other industry anywhere that has so many basic mishaps in terms of not delivering the basics," he said. "They're supposed to deliver passengers with their luggage to a particular destination within a certain timeframe, and they frequently fail to do that."
Asked why scores have worsened so significantly, he said airlines' management has to be blamed despite some factors beyond their control such as higher jet-fuel costs and congested airports.
But passengers also are not blameless, according to Fornell.
"They buy primarily on price, and very little else," he said. "The result of that is very low service and a business model of cost-cutting that really leaves no one happy, certainly not the businesses, the shareholders or the flying public."
About 26,000 people responded to the survey during the first quarter of this year, rating their level of satisfaction as customers of companies in a variety of industries, including airlines. An American Customer Satisfaction Index, on a scale of 1 to 100, was created based on the responses to questions about overall satisfaction, intention to be a repeat customer and perception of quality, value and expectations.
The index for the airline industry as a whole fell to 62 from 63 last year, barely above its historical low of 61 in 2001. Southwest led the way with an index of 79, up from 76 last year.
"We're always excited and thrilled that we can offer some of the best customer service in the industry," Southwest spokeswoman Christi Day said.
After Southwest came a huge drop in customer satisfaction, with scores of 62 at AMR Corp.'s American Airlines and Continental. Delta Air Lines Inc. scored 60, and Northwest Airlines Corp. slipped to 57 from 61 in 2007. US Airways' score dropped to 54 from 61 a year ago, taking over the bottom spot from United, whose score held at 56.
Tempe, Ariz.-based, US Airways acknowledged its need to improve.
"While we still have work to do, we're confident that the investments we're making in reliability, convenience and appearance are making a positive impact," spokesman Morgan Durrant said. He noted that the carrier had the best on-time performance of the 10 largest airlines in first-quarter statistics compiled by the U.S. Department of Transportation.
A spokeswoman for Chicago-based United, Robin Urbanski, said the carrier also recognized it has more work to do and is "working hard to fix the basics and provide a more consistent level of service."
Fornell said it is worrisome that the four big airlines looking to consolidate - Delta with Northwest, as agreed to last month, and United and US Airways - are at the bottom of the industry in customer satisfaction.
"When it comes to mergers, combining two negatives doesn't make a positive," he said.